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Updated: Jul 8, 2026
08:12
Surface Functionalization of Metal-Organic Frameworks for Improved Moisture Resistance
Published on: September 5, 2018
Two extended structures constructed from sandwich-type polyoxometalates functionalized by organic amines.
Zhiming Zhang1, Jia Liu, Enbo Wang
1Key Laboratory of Polyoxometalate Science of Ministry of Education, Department of Chemistry, Northeast Normal University, Changchun, Jilin 130024, P. R. China.
Dalton Transactions (Cambridge, England : 2003)
|January 11, 2008
Summary
Two novel polyoxometalate compounds with tetra-Ni substitution were synthesized. These materials exhibit unique 2D layer and 1D chain structures, revealing intramolecular ferromagnetic interactions in the metal clusters.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Crystallography
Background:
- Polyoxometalates (POMs) are versatile inorganic clusters with diverse structures and applications.
- Sandwich-type POMs, particularly those incorporating transition metals like nickel, offer tunable properties.
- Functionalization of POMs with organic groups can lead to novel supramolecular architectures.
Purpose of the Study:
- To synthesize and characterize new tetra-Ni-substituted sandwich-type polyoxometalates functionalized by organic groups.
- To investigate the crystal structures and supramolecular assembly of these novel compounds.
- To explore the magnetic properties arising from the nickel-metal clusters within the POM framework.
Main Methods:
- Hydrothermal synthesis was employed for the preparation of the target compounds.
- Single-crystal X-ray diffraction analysis was used to determine the detailed crystal structures.
- Magnetic susceptibility measurements were conducted to study the magnetic interactions.
Main Results:
- Two new compounds, (NH(4))(2)[Ni(4)(enMe)(8)(H(2)O)(2)Ni(4)(enMe)(2)(PW(9)O(34))(2)].9H(2)O (1) and Na(2)[H(6)N(2)(CH(2))(6)](2){Ni(4)[H(4)N(2)(CH(2))(6)](2)(H(2)PW(9)O(34))(2)}.7H(2)O (2), were successfully synthesized.
- Compound 1 features a 2D layer structure with organic functionalized sandwich-type polyoxoanions.
- Compound 2 displays a 1D chain structure that self-assembles into a 2D layer via hydrogen bonding, with intramolecular ferromagnetic Ni-Ni interactions observed.
Conclusions:
- The successful synthesis of novel organic-functionalized tetra-Ni-substituted sandwich-type polyoxometalates is reported.
- The study reveals distinct 2D layer and 1D chain structures, highlighting the role of organic linkers and hydrogen bonding in supramolecular assembly.
- The presence of intramolecular ferromagnetic Ni-Ni interactions in the tetranuclear metal clusters opens avenues for magnetic materials development.
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